mallocn.c

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/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#include <stdlib.h>
#include <string.h> /* memcpy */
#include <stdarg.h>
#include <sys/types.h>
/* Blame Microsoft for LLP64 and no inttypes.h, quick workaround needed: */
#if defined(WIN64)
#define SIZET_FORMAT "%I64u"
#define SIZET_ARG(a) ((unsigned long long)(a))
#else
#define SIZET_FORMAT "%lu"
#define SIZET_ARG(a) ((unsigned long)(a))
#endif

/* mmap exception */
#if defined(WIN32)
#include "mmap_win.h"
#else
#include <sys/mman.h>
#endif

#include "MEM_guardedalloc.h"

/* Only for debugging:
 * lets you count the allocations so as to find the allocator of unfreed memory
 * in situations where the leak is predictable */

// #define DEBUG_MEMCOUNTER

#ifdef DEBUG_MEMCOUNTER
#define DEBUG_MEMCOUNTER_ERROR_VAL 0 /* set this to the value that isnt being freed */
static int _mallocn_count = 0;

/* breakpoint here */
static void memcount_raise(const char *name)
{
    fprintf(stderr, "%s: memcount-leak, %d\n", name, _mallocn_count);
}
#endif

/* --------------------------------------------------------------------- */
/* Data definition                                                       */
/* --------------------------------------------------------------------- */
/* all memory chunks are put in linked lists */
typedef struct localLink
{
    struct localLink *next,*prev;
} localLink;

typedef struct localListBase 
{
    void *first, *last;
} localListBase;

    /* note: keep this struct aligned (e.g., irix/gcc) - Hos */
typedef struct MemHead {
    int tag1;
    size_t len;
    struct MemHead *next,*prev;
    const char * name;
    const char * nextname;
    int tag2;
    int mmap;   /* if true, memory was mmapped */
#ifdef DEBUG_MEMCOUNTER
    int _count;
#endif
} MemHead;

typedef struct MemTail {
    int tag3, pad;
} MemTail;


/* --------------------------------------------------------------------- */
/* local functions                                                       */
/* --------------------------------------------------------------------- */

static void addtail(volatile localListBase *listbase, void *vlink);
static void remlink(volatile localListBase *listbase, void *vlink);
static void rem_memblock(MemHead *memh);
static void MemorY_ErroR(const char *block, const char *error);
static const char *check_memlist(MemHead *memh);

/* --------------------------------------------------------------------- */
/* locally used defines                                                  */
/* --------------------------------------------------------------------- */

#ifdef __BIG_ENDIAN__
#  define MAKE_ID(a,b,c,d) ( (int)(a)<<24 | (int)(b)<<16 | (c)<<8 | (d) )
#else
#  define MAKE_ID(a,b,c,d) ( (int)(d)<<24 | (int)(c)<<16 | (b)<<8 | (a) )
#endif

#define MEMTAG1 MAKE_ID('M', 'E', 'M', 'O')
#define MEMTAG2 MAKE_ID('R', 'Y', 'B', 'L')
#define MEMTAG3 MAKE_ID('O', 'C', 'K', '!')
#define MEMFREE MAKE_ID('F', 'R', 'E', 'E')

#define MEMNEXT(x) ((MemHead *)(((char *) x) - ((char *) & (((MemHead *)0)->next))))
    
/* --------------------------------------------------------------------- */
/* vars                                                                  */
/* --------------------------------------------------------------------- */
    

static volatile int totblock= 0;
static volatile uintptr_t mem_in_use= 0, mmap_in_use= 0, peak_mem = 0;

static volatile struct localListBase _membase;
static volatile struct localListBase *membase = &_membase;
static void (*error_callback)(const char *) = NULL;
static void (*thread_lock_callback)(void) = NULL;
static void (*thread_unlock_callback)(void) = NULL;

static int malloc_debug_memset= 0;

#ifdef malloc
#undef malloc
#endif

#ifdef calloc
#undef calloc
#endif

#ifdef free
#undef free
#endif


/* --------------------------------------------------------------------- */
/* implementation                                                        */
/* --------------------------------------------------------------------- */

static void print_error(const char *str, ...)
{
    char buf[512];
    va_list ap;

    va_start(ap, str);
    vsnprintf(buf, sizeof(buf), str, ap);
    va_end(ap);
    buf[sizeof(buf) - 1] = '\0';

    if (error_callback) error_callback(buf);
}

static void mem_lock_thread(void)
{
    if (thread_lock_callback)
        thread_lock_callback();
}

static void mem_unlock_thread(void)
{
    if (thread_unlock_callback)
        thread_unlock_callback();
}

int MEM_check_memory_integrity(void)
{
    const char* err_val = NULL;
    MemHead* listend;
    /* check_memlist starts from the front, and runs until it finds
     * the requested chunk. For this test, that's the last one. */
    listend = membase->last;
    
    err_val = check_memlist(listend);

    if (err_val == NULL) return 0;
    return 1;
}


void MEM_set_error_callback(void (*func)(const char *))
{
    error_callback = func;
}

void MEM_set_lock_callback(void (*lock)(void), void (*unlock)(void))
{
    thread_lock_callback = lock;
    thread_unlock_callback = unlock;
}

void MEM_set_memory_debug(void)
{
    malloc_debug_memset= 1;
}

size_t MEM_allocN_len(void *vmemh)
{
    if (vmemh) {
        MemHead *memh= vmemh;
    
        memh--;
        return memh->len;
    } else
        return 0;
}

void *MEM_dupallocN(void *vmemh)
{
    void *newp= NULL;
    
    if (vmemh) {
        MemHead *memh= vmemh;
        memh--;
        
        if(memh->mmap)
            newp= MEM_mapallocN(memh->len, "dupli_mapalloc");
        else
            newp= MEM_mallocN(memh->len, "dupli_alloc");

        if (newp == NULL) return NULL;

        memcpy(newp, vmemh, memh->len);
    }

    return newp;
}

void *MEM_reallocN(void *vmemh, size_t len)
{
    void *newp= NULL;
    
    if (vmemh) {
        MemHead *memh= vmemh;
        memh--;

        newp= MEM_mallocN(len, memh->name);
        if(newp) {
            if(len < memh->len)
                memcpy(newp, vmemh, len);
            else
                memcpy(newp, vmemh, memh->len);
        }

        MEM_freeN(vmemh);
    }

    return newp;
}

static void make_memhead_header(MemHead *memh, size_t len, const char *str)
{
    MemTail *memt;
    
    memh->tag1 = MEMTAG1;
    memh->name = str;
    memh->nextname = NULL;
    memh->len = len;
    memh->mmap = 0;
    memh->tag2 = MEMTAG2;
    
    memt = (MemTail *)(((char *) memh) + sizeof(MemHead) + len);
    memt->tag3 = MEMTAG3;
    
    addtail(membase,&memh->next);
    if (memh->next) memh->nextname = MEMNEXT(memh->next)->name;
    
    totblock++;
    mem_in_use += len;

    peak_mem = mem_in_use > peak_mem ? mem_in_use : peak_mem;
}

void *MEM_mallocN(size_t len, const char *str)
{
    MemHead *memh;

    mem_lock_thread();

    len = (len + 3 ) & ~3;  /* allocate in units of 4 */
    
    memh= (MemHead *)malloc(len+sizeof(MemHead)+sizeof(MemTail));

    if(memh) {
        make_memhead_header(memh, len, str);
        mem_unlock_thread();
        if(malloc_debug_memset && len)
            memset(memh+1, 255, len);

#ifdef DEBUG_MEMCOUNTER
        if(_mallocn_count==DEBUG_MEMCOUNTER_ERROR_VAL)
            memcount_raise("MEM_mallocN");
        memh->_count= _mallocn_count++;
#endif
        return (++memh);
    }
    mem_unlock_thread();
    print_error("Malloc returns null: len=" SIZET_FORMAT " in %s, total %u\n", SIZET_ARG(len), str, mem_in_use);
    return NULL;
}

void *MEM_callocN(size_t len, const char *str)
{
    MemHead *memh;

    mem_lock_thread();

    len = (len + 3 ) & ~3;  /* allocate in units of 4 */

    memh= (MemHead *)calloc(len+sizeof(MemHead)+sizeof(MemTail),1);

    if(memh) {
        make_memhead_header(memh, len, str);
        mem_unlock_thread();
#ifdef DEBUG_MEMCOUNTER
        if(_mallocn_count==DEBUG_MEMCOUNTER_ERROR_VAL)
            memcount_raise("MEM_callocN");
        memh->_count= _mallocn_count++;
#endif
        return (++memh);
    }
    mem_unlock_thread();
    print_error("Calloc returns null: len=" SIZET_FORMAT " in %s, total %u\n", SIZET_ARG(len), str, mem_in_use);
    return NULL;
}

/* note; mmap returns zero'd memory */
void *MEM_mapallocN(size_t len, const char *str)
{
    MemHead *memh;

    mem_lock_thread();
    
    len = (len + 3 ) & ~3;  /* allocate in units of 4 */

    memh= mmap(NULL, len+sizeof(MemHead)+sizeof(MemTail),
            PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANON, -1, 0);

    if(memh!=(MemHead *)-1) {
        make_memhead_header(memh, len, str);
        memh->mmap= 1;
        mmap_in_use += len;
        peak_mem = mmap_in_use > peak_mem ? mmap_in_use : peak_mem;
        mem_unlock_thread();
#ifdef DEBUG_MEMCOUNTER
        if(_mallocn_count==DEBUG_MEMCOUNTER_ERROR_VAL)
            memcount_raise("MEM_mapallocN");
        memh->_count= _mallocn_count++;
#endif
        return (++memh);
    }
    else {
        mem_unlock_thread();
        print_error("Mapalloc returns null, fallback to regular malloc: len=" SIZET_FORMAT " in %s, total %u\n", SIZET_ARG(len), str, mmap_in_use);
        return MEM_callocN(len, str);
    }
}

/* Memory statistics print */
typedef struct MemPrintBlock {
    const char *name;
    uintptr_t len;
    int items;
} MemPrintBlock;

static int compare_name(const void *p1, const void *p2)
{
    const MemPrintBlock *pb1= (const MemPrintBlock*)p1;
    const MemPrintBlock *pb2= (const MemPrintBlock*)p2;

    return strcmp(pb1->name, pb2->name);
}

static int compare_len(const void *p1, const void *p2)
{
    const MemPrintBlock *pb1= (const MemPrintBlock*)p1;
    const MemPrintBlock *pb2= (const MemPrintBlock*)p2;

    if(pb1->len < pb2->len)
        return 1;
    else if(pb1->len == pb2->len)
        return 0;
    else
        return -1;
}

void MEM_printmemlist_stats(void)
{
    MemHead *membl;
    MemPrintBlock *pb, *printblock;
    int totpb, a, b;

    mem_lock_thread();

    /* put memory blocks into array */
    printblock= malloc(sizeof(MemPrintBlock)*totblock);

    pb= printblock;
    totpb= 0;

    membl = membase->first;
    if (membl) membl = MEMNEXT(membl);

    while(membl) {
        pb->name= membl->name;
        pb->len= membl->len;
        pb->items= 1;

        totpb++;
        pb++;

        if(membl->next)
            membl= MEMNEXT(membl->next);
        else break;
    }

    /* sort by name and add together blocks with the same name */
    qsort(printblock, totpb, sizeof(MemPrintBlock), compare_name);
    for(a=0, b=0; a<totpb; a++) {
        if(a == b) {
            continue;
        }
        else if(strcmp(printblock[a].name, printblock[b].name) == 0) {
            printblock[b].len += printblock[a].len;
            printblock[b].items++;
        }
        else {
            b++;
            memcpy(&printblock[b], &printblock[a], sizeof(MemPrintBlock));
        }
    }
    totpb= b+1;

    /* sort by length and print */
    qsort(printblock, totpb, sizeof(MemPrintBlock), compare_len);
    printf("\ntotal memory len: %.3f MB\n", (double)mem_in_use/(double)(1024*1024));
    printf(" ITEMS TOTAL-MiB AVERAGE-KiB TYPE\n");
    for(a=0, pb=printblock; a<totpb; a++, pb++)
        printf("%6d (%8.3f  %8.3f) %s\n", pb->items, (double)pb->len/(double)(1024*1024), (double)pb->len/1024.0/(double)pb->items, pb->name);

    free(printblock);
    
    mem_unlock_thread();

#if 0 /* GLIBC only */
    malloc_stats();
#endif
}

/* Prints in python syntax for easy */
static void MEM_printmemlist_internal( int pydict )
{
    MemHead *membl;

    mem_lock_thread();

    membl = membase->first;
    if (membl) membl = MEMNEXT(membl);
    
    if (pydict) {
        print_error("# membase_debug.py\n");
        print_error("membase = [\\\n");
    }
    while(membl) {
        if (pydict) {
            fprintf(stderr, "{'len':" SIZET_FORMAT ", 'name':'''%s''', 'pointer':'%p'},\\\n", SIZET_ARG(membl->len), membl->name, (void *)(membl+1));
        } else {
#ifdef DEBUG_MEMCOUNTER
            print_error("%s len: " SIZET_FORMAT " %p, count: %d\n", membl->name, SIZET_ARG(membl->len), membl+1, membl->_count);
#else
            print_error("%s len: " SIZET_FORMAT " %p\n", membl->name, SIZET_ARG(membl->len), membl+1);
#endif
        }
        if(membl->next)
            membl= MEMNEXT(membl->next);
        else break;
    }
    if (pydict) {
        fprintf(stderr, "]\n\n");
        fprintf(stderr,
"mb_userinfo = {}\n"
"totmem = 0\n"
"for mb_item in membase:\n"
"\tmb_item_user_size = mb_userinfo.setdefault(mb_item['name'], [0,0])\n"
"\tmb_item_user_size[0] += 1 # Add a user\n"
"\tmb_item_user_size[1] += mb_item['len'] # Increment the size\n"
"\ttotmem += mb_item['len']\n"
"print '(membase) items:', len(membase), '| unique-names:', len(mb_userinfo), '| total-mem:', totmem\n"
"mb_userinfo_sort = mb_userinfo.items()\n"
"for sort_name, sort_func in (('size', lambda a: -a[1][1]), ('users', lambda a: -a[1][0]), ('name', lambda a: a[0])):\n"
"\tprint '\\nSorting by:', sort_name\n"
"\tmb_userinfo_sort.sort(key = sort_func)\n"
"\tfor item in mb_userinfo_sort:\n"
"\t\tprint 'name:%%s, users:%%i, len:%%i' %% (item[0], item[1][0], item[1][1])\n"
        );
    }
    
    mem_unlock_thread();
}

void MEM_callbackmemlist(void (*func)(void*)) {
    MemHead *membl;

    mem_lock_thread();

    membl = membase->first;
    if (membl) membl = MEMNEXT(membl);

    while(membl) {
        func(membl+1);
        if(membl->next)
            membl= MEMNEXT(membl->next);
        else break;
    }

    mem_unlock_thread();
}

short MEM_testN(void *vmemh) {
    MemHead *membl;

    mem_lock_thread();

    membl = membase->first;
    if (membl) membl = MEMNEXT(membl);

    while(membl) {
        if (vmemh == membl+1) {
            mem_unlock_thread();
            return 1;
        }

        if(membl->next)
            membl= MEMNEXT(membl->next);
        else break;
    }

    mem_unlock_thread();

    print_error("Memoryblock %p: pointer not in memlist\n", vmemh);
    return 0;
}

void MEM_printmemlist( void ) {
    MEM_printmemlist_internal(0);
}
void MEM_printmemlist_pydict( void ) {
    MEM_printmemlist_internal(1);
}

short MEM_freeN(void *vmemh)        /* anders compileertie niet meer */
{
    short error = 0;
    MemTail *memt;
    MemHead *memh= vmemh;
    const char *name;

    if (memh == NULL){
        MemorY_ErroR("free","attempt to free NULL pointer");
        /* print_error(err_stream, "%d\n", (memh+4000)->tag1); */
        return(-1);
    }

    if(sizeof(intptr_t)==8) {
        if (((intptr_t) memh) & 0x7) {
            MemorY_ErroR("free","attempt to free illegal pointer");
            return(-1);
        }
    }
    else {
        if (((intptr_t) memh) & 0x3) {
            MemorY_ErroR("free","attempt to free illegal pointer");
            return(-1);
        }
    }
    
    memh--;
    if(memh->tag1 == MEMFREE && memh->tag2 == MEMFREE) {
        MemorY_ErroR(memh->name,"double free");
        return(-1);
    }

    mem_lock_thread();
    if ((memh->tag1 == MEMTAG1) && (memh->tag2 == MEMTAG2) && ((memh->len & 0x3) == 0)) {
        memt = (MemTail *)(((char *) memh) + sizeof(MemHead) + memh->len);
        if (memt->tag3 == MEMTAG3){
            
            memh->tag1 = MEMFREE;
            memh->tag2 = MEMFREE;
            memt->tag3 = MEMFREE;
            /* after tags !!! */
            rem_memblock(memh);

            mem_unlock_thread();
            
            return(0);
        }
        error = 2;
        MemorY_ErroR(memh->name,"end corrupt");
        name = check_memlist(memh);
        if (name != NULL){
            if (name != memh->name) MemorY_ErroR(name,"is also corrupt");
        }
    } else{
        error = -1;
        name = check_memlist(memh);
        if (name == NULL)
            MemorY_ErroR("free","pointer not in memlist");
        else
            MemorY_ErroR(name,"error in header");
    }

    totblock--;
    /* here a DUMP should happen */

    mem_unlock_thread();

    return(error);
}

/* --------------------------------------------------------------------- */
/* local functions                                                       */
/* --------------------------------------------------------------------- */

static void addtail(volatile localListBase *listbase, void *vlink)
{
    struct localLink *link= vlink;

    if (link == NULL) return;
    if (listbase == NULL) return;

    link->next = NULL;
    link->prev = listbase->last;

    if (listbase->last) ((struct localLink *)listbase->last)->next = link;
    if (listbase->first == NULL) listbase->first = link;
    listbase->last = link;
}

static void remlink(volatile localListBase *listbase, void *vlink)
{
    struct localLink *link= vlink;

    if (link == NULL) return;
    if (listbase == NULL) return;

    if (link->next) link->next->prev = link->prev;
    if (link->prev) link->prev->next = link->next;

    if (listbase->last == link) listbase->last = link->prev;
    if (listbase->first == link) listbase->first = link->next;
}

static void rem_memblock(MemHead *memh)
{
    remlink(membase,&memh->next);
    if (memh->prev) {
        if (memh->next)
            MEMNEXT(memh->prev)->nextname = MEMNEXT(memh->next)->name;
        else
            MEMNEXT(memh->prev)->nextname = NULL;
    }

    totblock--;
    mem_in_use -= memh->len;

    if(memh->mmap) {
        mmap_in_use -= memh->len;
        if (munmap(memh, memh->len + sizeof(MemHead) + sizeof(MemTail)))
            printf("Couldn't unmap memory %s\n", memh->name);
    }
    else {
        if(malloc_debug_memset && memh->len)
            memset(memh+1, 255, memh->len);
        free(memh);
    }
}

static void MemorY_ErroR(const char *block, const char *error)
{
    print_error("Memoryblock %s: %s\n",block, error);

#ifdef WITH_ASSERT_ABORT
    abort();
#endif
}

static const char *check_memlist(MemHead *memh)
{
    MemHead *forw,*back,*forwok,*backok;
    const char *name;

    forw = membase->first;
    if (forw) forw = MEMNEXT(forw);
    forwok = NULL;
    while(forw){
        if (forw->tag1 != MEMTAG1 || forw->tag2 != MEMTAG2) break;
        forwok = forw;
        if (forw->next) forw = MEMNEXT(forw->next);
        else forw = NULL;
    }

    back = (MemHead *) membase->last;
    if (back) back = MEMNEXT(back);
    backok = NULL;
    while(back){
        if (back->tag1 != MEMTAG1 || back->tag2 != MEMTAG2) break;
        backok = back;
        if (back->prev) back = MEMNEXT(back->prev);
        else back = NULL;
    }

    if (forw != back) return ("MORE THAN 1 MEMORYBLOCK CORRUPT");

    if (forw == NULL && back == NULL){
        /* geen foute headers gevonden dan maar op zoek naar memblock*/

        forw = membase->first;
        if (forw) forw = MEMNEXT(forw);
        forwok = NULL;
        while(forw){
            if (forw == memh) break;
            if (forw->tag1 != MEMTAG1 || forw->tag2 != MEMTAG2) break;
            forwok = forw;
            if (forw->next) forw = MEMNEXT(forw->next);
            else forw = NULL;
        }
        if (forw == NULL) return NULL;

        back = (MemHead *) membase->last;
        if (back) back = MEMNEXT(back);
        backok = NULL;
        while(back){
            if (back == memh) break;
            if (back->tag1 != MEMTAG1 || back->tag2 != MEMTAG2) break;
            backok = back;
            if (back->prev) back = MEMNEXT(back->prev);
            else back = NULL;
        }
    }

    if (forwok) name = forwok->nextname;
    else name = "No name found";

    if (forw == memh){
        /* voor alle zekerheid wordt dit block maar uit de lijst gehaald */
        if (forwok){
            if (backok){
                forwok->next = (MemHead *)&backok->next;
                backok->prev = (MemHead *)&forwok->next;
                forwok->nextname = backok->name;
            } else{
                forwok->next = NULL;
                membase->last = (struct localLink *) &forwok->next;
/*                  membase->last = (struct Link *) &forwok->next; */
            }
        } else{
            if (backok){
                backok->prev = NULL;
                membase->first = &backok->next;
            } else{
                membase->first = membase->last = NULL;
            }
        }
    } else{
        MemorY_ErroR(name,"Additional error in header");
        return("Additional error in header");
    }

    return(name);
}

uintptr_t MEM_get_peak_memory(void)
{
    uintptr_t _peak_mem;

    mem_lock_thread();
    _peak_mem = peak_mem;
    mem_unlock_thread();

    return _peak_mem;
}

void MEM_reset_peak_memory(void)
{
    mem_lock_thread();
    peak_mem = 0;
    mem_unlock_thread();
}

uintptr_t MEM_get_memory_in_use(void)
{
    uintptr_t _mem_in_use;

    mem_lock_thread();
    _mem_in_use= mem_in_use;
    mem_unlock_thread();

    return _mem_in_use;
}

uintptr_t MEM_get_mapped_memory_in_use(void)
{
    uintptr_t _mmap_in_use;

    mem_lock_thread();
    _mmap_in_use= mmap_in_use;
    mem_unlock_thread();

    return _mmap_in_use;
}

int MEM_get_memory_blocks_in_use(void)
{
    int _totblock;

    mem_lock_thread();
    _totblock= totblock;
    mem_unlock_thread();

    return _totblock;
}

#ifndef NDEBUG
const char *MEM_name_ptr(void *vmemh)
{
    if (vmemh) {
        MemHead *memh= vmemh;
        memh--;
        return memh->name;
    }
    else {
        return "MEM_name_ptr(NULL)";
    }
}
#endif

/* eof */